STLED325QTR STMicroelectronics, STLED325QTR Datasheet - Page 26

• Manufacturer Part Number: STLED325QTR
• Description: LED Lighting Drivers I2C interfaced LED controller/driver
• Manufacturer: STMicroelectronics

Specifications of STLED325QTR

• Product Category: LED Lighting Drivers
• Rohs: yes
• Input Voltage: 5 V
• Maximum Supply Current: 2 mA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-32
• Minimum Operating Temperature: - 40 C
• Power Dissipation: 1200 mW

Functional description
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Remote control decoder
The remote control (RC) decoder module decodes the signal coming from IR_IN pin. The IR
remote control protocols recognized by STLED325 are Philips-RC-5, RCMM, Thomson
RCA, R2000, NEC and R-STEP protocols. The selection of remote control protocol to use is
done by setting the RC protocols register. The command from the remote control is used to
wake-up from standby and resume normal operation. All RC keys can be programmed to act
like RC hotkeys. Upon receiving any one of the designated hotkeys, wake-up operation
begins.
The address of the appliance (8-bit) is stored first into the internal RAM. Then, the command
for the hotkeys is programmed into the internal RAM. Each hotkey memory address could
accommodate one byte (8-bit). Usually one byte is reserved for one command. The hot-keys
can be configured to wake-up the system by more than one RC device address (up to a
maximum of 8 device addresses).
Interrupt
The STLED325 interrupts the Host by pulling the IRQ_N pin to a low-level both in normal
mode of operation and during wake-up. The interrupt is enabled by STLED325 when any of
the conditions occur:
The IRQ_N is an active low level signal and is cleared only after the Interrupt buffer is read.
After reading the interrupt buffer, the Host will know the actual source of the interrupt. This
allows the Host to exactly know the event which caused the interrupt (e.g STBY key on the
Front Panel). The interrupt signal is used to inform the Host of any events detected by the
STLED325. Note that the IRQ_N pin is an open-drain pin which requires an external pull-up
resistor.
Figure 9.
The interrupt output is of active low level type.
– Front panel key press in normal operation or during system standby state
– Remote control key press in normal operation or during system standby state
– A low-to-high on the external pin, WAKE_UP
– Real time clock triggers (alarm, watchdog timer, 32 kHz oscillator fails)
– GPIO input changes
– Low battery indication
– Thermal shutdown
(including the toggle bit changes for all RC protocols)
Interrupt
Doc ID 17576 Rev 1
STLED325